This article implements and validates the performance of a virtual intelligent electronic device (vIED) framework for digital substations using a real-time (RT) simulation environment. The work looks toward the future design of protection, automation, and control systems, an evolution of the digital substation design based on IEC 61850 and virtualization technology. An RT simulation setup was developed to speed up and enhance the deployment and maintenance of vIEDs with a novel well-defined test methodology. Several scenarios were tested by varying the number of vIEDs and relevant (communication, scalability, and functionality) configuration criteria. In addition, we assessed the efficiency of a software-defined communication network for the vIED framework and its adaptability to dynamic scaling of the network under transient data traffic loads. The tests demonstrated the efficient performance of vIEDs across various system configurations, particularly for requirements on the response time and network transfer latency. The findings showcase the significance of proper design and testing methodology that can be benchmarked against other virtualization platforms for substation systems.

This paper studies the inclusion of averaged VSC-based grid interfaces and HVDC networks into stability type simulations, and compares the accuracy and speed of three multi-terminal DC dynamic models: 1) a state-space based model, 2) a multi-rate improved model, and 3) a reduced-order model. The accuracy comparison is conducted by qualitative time-domain analysis taking the state-space model as a reference whereas the computational aspects are investigated by the respective execution times. The models are demonstrated on a three VSC terminal, two synchronous area system. It is shown that the reduced-order model is too inaccurate to investigate detailed large-disturbance stability-related dynamics. The multi-rate model shows the best trade-off between simulation accuracy and speed.

This paper deals with the inclusion of VSC-HVdc transmission schemes into stability-type simulations by hybrid methods. These methods allow selected parts of the network to be simulated in detail by including electro-magnetic behaviour of devices and network elements whereas the remainder of the network is simulated in a simplified fashion with emphasis on electro-mechanical interactions. The paper discusses the interface methods needed for coupling both simulations, and presents a simple but robust interface, particularly designed for VSCs. Several aspects that determine the performance of the hybrid simulation are discussed and tested by simulations on an example network. The hybrid simulations have been implemented in Matlab and verified against a full EMT-type simulation in PSS®NETOMAC.

Abstract In this paper, we investigate the possibility of integrating 12 GW of onshore and offshore wind energy in the power system of the Netherlands. Interconnection capacities to the rest of the synchronous UCTE system and HVDC connections to Great Britain and Norway are modelled as flow gates, while sufficient transmission capacity for integrating wind is assumed to be present within the Dutch system itself. For this case study, we use realistic time series of aggregated 15-minute wind power production and forecast, based on one year of wind speed measurements and forecasts at various locations in the Netherlands and its coastal waters, and multi-turbine wind farm models. The technical capabilities of the foreseen conventional generation portfolios of the Netherlands and its neighbouring countries are modelled in detail, in terms of ramping abilities, fuel efficiency, and minimum up and down times. Particular attention is also paid to wind energy developments in Germany, since high correlations exist between the wind power outputs of the two countries. A preliminary evaluation in terms of margin at peak load, minimum load problems, and ability of conventional units to follow the load less wind variations is made, based on the net load duration curves of Netherlands and Germany in 2020. It is shown that smaller amounts of wasted wind (i.e. wind energy that cannot be taken by the system) due to minimum load problems occur when exchanges of excess wind energy can be scheduled between the two countries close to the operation time. This shows the importance of having larger geographic areas and well-organized cross-border trading to facilitate larger amounts of integrated wind energy. However, wasted wind cannot be completely avoided due to correlations in low load - high wind situations between the two countries. These results are confirmed through detailed chronological simulations of one year of operation, using a unit commitment and economic dispatch tool specifically ada- pted to perform wind integration studies. The potential for demand-side management to allow for a better integration of wind power is briefly explored.